In 1410, the UNN requisitioned the design of a multi purpose tank chassis that could be equipped with antitank, -air and -infantry armament alike. With the availability of the new V-engine technology, bigger and heavier tank designs entered the realm of possibility, and the T-No. 11's design was the first to capitalise on it.

The first prototype entered its testing phase in February 1411, less than a month after the (partial) annexation of Podotsk and Minegorod. During the invasion, the UNN came face to face with the ZM.L-1/37 and its fearsome 37mm breach loaded cannon. The UNN's armored invading force was comprised of the agile but ill-armored Mark 1 and Mark 2 series, which were not designed for tank vs tank combat. In a fair standoff against the ZM.L-1/37, the Mark 1 and Mark 2 would be quickly disposed of. Testing of the T-No.11 was accelerated as a direct result.

UNN engineers managed to reverse engineer a captured 37mm and improve on the technology. The weapon was equipped with a rapid firing mechanism, turning the 37mm breach loaded cannon into a magazine loaded semi-automatic large calibre weapon. It could fire five shells in rapid succession, but it lost some penetrating power as a result. Nevertheless, the weapon was deemed effective enough to be deployed with the T-No.11 chassis. The vehicle completed testing in May 1411 and entered full scale production shortly after.

Tank to tank combat was not something that was commonly seen before the Novourovan War, and the T.No-11 was the first UNN produced tank that was equipped to deal with the new threat appropriately. It was the first of a new generation of armored fighting vehicles and the first to receive the new T.No designation. The semiautomatic 37mm was not without flaws, but its penetrating properties and rapid fire ability proved to be devastating against its Novourova Liberta (NL) counterpart, the ZM.L-1/37.

The versatile T-No.11 chassis allowed for several adaptations outfitted for different roles. The first and most common adaptation received the designation 'mark II'. The rotating turret and 37mm semiautomatic cannon were replaced with a fixed weapon assembly and armor plating. This adaptation allowed for heavier weapons to be installed without sacrificing survivability, mobility and ammo capacity. The adaptation required no significant changes to the chassis itself, which meant that a T.No-11 could easily be converted to a mark II if its turret or weapon was damaged in battle.